The present invention relates to electronics assemblies, and is primarily concerned with racked assemblies. Many such assemblies will be located in racks for housing in for example nineteen inch cabinets, or other size cabinets such as twenty three inch or metric cabinets. The assemblies may for instance be employed as servers for a number of systems, for example in local area networks (LANs), wide area networks (WANs), telecommunications systems or other operations such as database management or as internet servers.
Such an assembly will typically comprise a supporting frame that houses a motherboard or backplane and a number of daughterboards or module cards that extend in planes generally perpendicular to the plane of the motherboard and which are connected to the motherboard by connectors, e.g. high density connectors, so that the daughterboards can simply be located on guides and pushed toward the motherboard in order to connect them to it.
One form of assembly that is intended to act as a server and which is currently under development, is intended as far as possible to be in continuous operation and therefore has a plurality of power supply units that can receive, for example, mains a.c. power (although d.c. power supply units are an option) and deliver d.c. power at the appropriate working voltage to the motherboard and to any other circuitry in the assembly. Each power supply unit therefore usually has a transformer, rectifier, control circuitry and a dedicated cooling fan. In addition, more power supply units than necessary for operation of the assembly are provided in order to provide a degree of redundancy that will allow one or more supplies to be replaced without interruption of functioning of the server.
In addition, it is desirable to guard against the system going down in the event of a power failure in part of the building in which the assembly is located, either due for example to fusing of a ring circuit in the building or to inadvertent unplugging of the assembly from a mains power socket. For this reason power is intended to be taken from more than one ring circuit of the building and fed into a power input connection arrangement in which power can be supplied from each mains input to any of the power supply units as circumstances demand. This power inlet connection arrangement is in the form of a module having a number of power input connectors on an input side thereof and a number of power output connectors (one for each power supply unit) on an input side. In this way the system is guarded as far as practicable, against power failure, either due to failure of power supply or to failure of any internal systems. The modules typically have a rectangular cross-section and are normally 10 to 20 cm in length having their connectors rigidly located at an end thereof so that the modules can be inserted into an appropriate recess in the frame and connected directly to the other module, whether the power supply module or the power inlet connection module, and an electrical connection be formed simply by pushing. Accordingly the electrical connectors are push-fit (usually mains voltage) connectors, for example according to IEC 320.
According to the proposed server design, four power supply modules are intended to be fed by the power inlet connection module, the power inlet connection module being installed by sliding it into a recess at the rear of the frame, and the four power supply modules being installed by sliding them into the front of the frame.
However, it has proved very difficult to connect the power supply modules and the power inlet connection module together correctly, due mainly to the fact that the modules have to be blind mated, that is to say, they are mated in the centre of the frame to which the engineer has no access or vision during mating. Furthermore the form of plug and socket connection that is most commonly employed, the IEC 320 connector, is not intended for this type of use but instead is intended for use in circumstances where the plug or socket can be manually grasped and manipulated during connection.
According to one aspect, the present invention provides an electronics assembly which comprises:
(i) a frame;
(ii) a plurality of power supply modules for supplying power to electrical circuitry of the assembly, each of which has an input power connector and an output power connector; and
(iii) a power inlet connection module which is electrically connected to a plurality of the power supply modules;
wherein the power inlet connection module is separated from the power supply modules by an internal wall of the frame which has, on one side thereof, at least one location element for locating the power inlet connection module relative to the wall and, on the other side thereof, at least one location element for locating each power supply module that is connected to the power inlet connection module relative to the wall so that the power supply modules are aligned with the power inlet connection module by means of the internal wall.
This form of assembly has the advantage that it is possible relatively easily for a service engineer to replace any of the power supply modules or the power inlet connection modules and to connect the replacement module to the remaining modules with a minimum of effort.
The power supply modules may be stacked together within the frame, normally within their own individual slide-in recesses, and will usually together occupy a volume of the same height and width as that of the power inlet connection module.
It is possible for more than one power inlet connection modules to be employed if, for example, a large number of power supply modules were being supplied, but in most cases only a single power inlet connection module will be needed, which will be connected to all the power supply modules.
The power supply modules are usually designed to have their input power connectors and their output power connector on the same surface thereof. This enables all the input power connectors to be aligned with a bank of input power sockets on the power inlet connection module, and for the d.c. output power connectors of each power supply module to be connected to a common power distribution circuit board. The power inlet connection module will typically be generally flat since it will have a shape to enable it to mate with a number of power supply modules that are stacked together, in which case the power distribution circuit board is conveniently arranged next to the power inlet connection module and in a plane parallel to the plane thereof.
The location elements on the internal wall of the frame which engage corresponding surfaces or elements on the various modules are normally separate from any electrical connector thereof so that the modules as a whole are guided into their correct position during installation thereof. The location elements on at least one side of the internal wall, and preferably on both sides thereof, are preferably in the form of a pin that can engage a corresponding recess in the relevant module. The pins will normally have a tapered end in order to provide a degree of lateral guidance during insertion of the modules. In addition, the location element corresponding to the power inlet connection module and/or each power supply module is preferably offset from an axis of symmetry of the module in order to ensure correct orientation of the module with respect to the frame.
The internal wall of the frame may be mechanically connected to the motherboard with a relatively tight tolerance in order to enable accurate alignment to be achieved with other components in the system and especially in order to achieve accurate alignment between the power distribution board connectors and the motherboard connectors. In addition, it is possible for the power distribution board to be mechanically connected to the internal wall or the location element for the power inlet connection module, either directly or via card guides for the power distribution board, in order to provide accurate alignment of the connectors on the power distribution board with those on the power supply modules.
According to another aspect, the invention provides a frame for an electronics assembly which comprises:
(i) a first location in which a plurality of power supply modules can be received; and
(ii) a second location in which a power inlet connection module can be received so that it is electrically connectable to each of a number of power supply modules received in said first location;
wherein the first location and the second location are separated from one another by an internal wall of the frame, the wall having on one side thereof at least one location element for locating the power inlet connection module, and, on the other side thereof, at least one location element for locating each power supply module so that, when the power supply modules and the power inlet connection module are received in the frame they are aligned with one another by the wall.
According to a further aspect, the invention provides a method of blind mating of modules in an electronics assembly which comprises a frame having a first location in which a plurality of power supply modules can be received, and a second location in which a power inlet connection module can be received so that it is electrically connectable to each of a number of power supply modules in the first location, wherein the first location and the second location are separated from one another by an internal wall of the frame, the wall having on one side thereof at least one location element for locating the power inlet connection module and, on the other side thereof, at least one location element for locating each power supply module, the method comprising sliding the power inlet connection module into the second location and the power supply modules into the first location so that the power inlet connection module and the power supply modules are guided into their correct relative position and into mating engagement by the location elements on the wall.
According to yet another aspect, the invention provides a power inlet connection module for an electronics assembly, the module having a number of power inlet connectors on an input side thereof and a number of power output connectors on an output side thereof such that electrical power can be supplied to any of the power output connectors from any one or more of the power inpet connectors, and the module has on the output side thereof a location element to allow the module to be inserted into a recess in a frame of an electronics assembly and guided by engagement of the location element with a corresponding location element at a distal end of the recess.
It is believed that the wall employed in the present invention is novel per se and so, according to yet a further aspect, the invention provides a wall for mounting in an electronics rack carcase which includes at least one locating element on one side thereof for guiding and locating a power inlet distribution module that is received by the rack, and a plurality of locating elements on the other side thereof for guiding and locating a plurality of power supply modules that are received by the rack, so that the power inlet distribution module and the power supply modules can be inserted into opposite sides of the rack and guided into mating engagement by the location elements on the wall.